Prevalence of Sarcopenia in Stroke Patients

ASMMI is defined as appendicular skeletal muscle mass(kg)/height (m^2). This study utilizes BIA for body muscle mass measurement, considering the accessibility of the equipment and budget constraints.

In this study, grip strength is measured using a JAMAR electronic dynamometer, with a minimum scale of 0.1 pounds. The testing procedure is as follows:

The participant is seated with the shoulder in a neutral position, the upper arm relaxed alongside the body, and the elbow flexed at a 90-degree angle. The participant holds the JAMAR dynamometer with their dominant hand. They are instructed to gradually apply force, reaching their maximum grip strength within 3 seconds.

Before the test, a practice trial is provided to ensure the participant understands the procedure. The grip strength is tested twice, with a 30-second rest between trials. The average of the two trials is recorded as the final result

The testing procedure is as follows: A stopwatch is used to measure the time (in seconds) from the command "Ready, go" until the participant crosses a 6-meter distance marked on the floor. Two trials are conducted, with a 10-minute rest between each trial. Walking speed (m/s) is calculated for each trial, and the average of the two trials is used for data analysis.

In this study, the maximal voluntary isometric contraction (MVIC) strength of the dominant quadriceps muscle is measured using the MicroFET3 device (Hoggan, Health Industrial, UT, USA) under standardized posture. The average of two measurements is recorded as the participant's MVIC strength.

In this study, a portable ultrasound device, equipped with a 12 MHz linear probe, is used for measurements. All measurements are performed under the same parameter settings by a physician with years of clinical ultrasound experience.

The measurement of the quadriceps muscle is conducted with participants in a supine position, with both lower limbs extended and fully relaxed. The probe is placed at the midpoint of the line connecting the anterior superior iliac spine (ASIS) and the superior border of the patella (see illustration on the left). The thickness of the quadriceps muscle is defined as the sum of the thickness of the rectus femoris and vastus intermedius muscles, measured in a transverse scan.

In this study, a portable ultrasound device, equipped with a 12 MHz linear probe, is used for measurements. All measurements are performed under the same parameter settings by a physician with years of clinical ultrasound experience.

The measurement of the gastrocnemius muscle is performed with participants in a prone position, both legs extended and relaxed, with the feet hanging off the edge of the examination table. The examiner places the ultrasound probe close to the skin, ensuring the probe beam is perpendicular to the skin surface. The medial cross-sectional area of the medial head of the gastrocnemius muscle is identified, with the largest cross-sectional area selected as the standard imaging plane, and the corresponding skin surface location is marked.

Measurements include:

• Fat thickness (FT): The distance from the superficial fascia to the skin.
• Muscle thickness (MT): The distance from the superficial fascia to the deep fascia.

The measurement of calf circumference (CC) is conducted bilaterally, including the paretic and non-paretic sides of stroke patients. Participants are positioned in either a seated or supine posture, with the knees and hips flexed at 90°, and the feet naturally placed on the floor or bed, with the ankles relaxed. The examiner faces the participant and identifies the largest circumference of the calf on both sides.

A flexible tape measure is used to measure CC, ensuring it is positioned perpendicular to the axis of the calf. The measurement error is kept below 0.1 cm. To minimize the influence of edema, measurements are performed in the morning. Each leg is measured twice, and the highest value is recorded.

Sarcopenia risk was assessed using the Strength, Assistance with walking, Rise from a chair, Climb stairs, and Falls (SARC-F) questionnaire, a 5-item screening tool based on participant self-reported responses. Each item is scored from 0 to 2, with a total score ranging from 0 to 10.

Higher scores indicate a greater risk of sarcopenia, and a score ≥4 suggests probable sarcopenia. The SARC-F questionnaire is designed for use in clinical and community settings without requiring specialized equipment, making it suitable for large-scale screening.

The total SARC-F score was analyzed as a continuous variable.

Nutritional status was assessed using the Mini Nutritional Assessment (MNA), an 18-item standardized tool evaluating dietary intake, anthropometric measurements, and general health status. The total score ranges from 0 to 30.

Based on established cutoffs, scores ≥24 indicate normal nutritional status, scores between 17 and 23.5 indicate risk of malnutrition, and scores <17 indicate malnutrition.

The total MNA score was analyzed as a continuous variable.

Health-related quality of life was assessed using the EuroQol 5-Dimension 3-Level (EQ-5D-3L) questionnaire, which evaluates five domains: mobility, self-care, usual activities, pain/discomfort, and anxiety/depression.

An EQ-5D index score was calculated using the Taiwan-specific value set. The index score ranges from -0.111 to 1.000, with higher scores indicating better health-related quality of life.

The EQ-5D index score was analyzed as a continuous variable.

EQ-5D-VAS, in which participants rate their overall health status on a scale from 0 to 100.

A score of 0 represents the worst imaginable health state, and a score of 100 represents the best imaginable health state.

The EQ-5D VAS score was analyzed as a continuous variable, with higher scores indicating better perceived health status.